• 제목/요약/키워드: principle components

검색결과 455건 처리시간 0.03초

3-Dimensional Performance Optimization Model of Snatch Weightlifting

  • Moon, Young-Jin;Darren, Stefanyshyn
    • 한국운동역학회지
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    • 제25권2호
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    • pp.157-165
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    • 2015
  • Object : The goals of this research were to make Performance Enhanced Model(PE) taken the largest performance index (PI) through artificial variation of principle components calculated by principle component analysis for trial data, and to verify the effect through comparing kinematic factors between trial data (Raw) and PE. Method : Ten subjects (5 men, 5 women) were recruited and 80% of their maximal record was considered. The PI is a regression equation. In order to develop PE, we extracted Principle components from trial position data (by Principle Components Analysis (PCA)). Before PCA, we made 17 position data to 3 row matrix according to components. We calculated 3 eigen value (principle components) through PCA. And except Y (medial-lateral direction) component (because motion of Y component is small), principle components of X (anterior-posterior direction) and Z (vertical direction) components were changed as following. Changed principle components = principle components + principle components ${\times}$ k. After changing the each principle component, we reconstructed position data using the changed principle components and calculated performance index (PI). A Paired t-test was used to compare Raw data and Performance Enhanced Model data. The level of statistical significance was set at $p{\leq}0.05$. Result : The PI was significantly increased about 12.9kg at PE ($101.92{\pm}6.25$) when compared to the Raw data ($91.29{\pm}7.10$). It means that performance can be increased by optimizing 3D positions. The difference of kinematic factors as follows : the movement distance of the bar from start to lock out was significantly larger (about 1cm) for PE, the width of anterior-posterior bar position in full phase was significantly wider (about 1.3cm) for PE and the horizontal displacement toward the weightlifter after beginning of descent from maximal height was significantly greater (about 0.4cm) for PE. Additionally, the minimum knee angle in the 2-pull phase was significantly smaller (approximately 2.7cm) for the PE compared to that of the Raw. PE was decided at proximal position from the Raw (origin point (0,0)) of PC variation). Conclusion : PI was decided at proximal position from the Raw (origin point (0,0)) of PC variation). This means that Performance Enhanced Model was decided by similar motion to the Raw without a great change. Therefore, weightlifters could be accept Performance Enhanced Model easily, comfortably and without large stress. The Performance Enhance Model can provide training direction for athletes to improve their weightlifting records.

서비스 경영 혁신 기업 평가 모형의 개선 방안 연구 (A Research on Improving the Evaluation Model for Management Innovative Enterprises)

  • 노재확
    • 통상정보연구
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    • 제12권4호
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    • pp.279-302
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    • 2010
  • A better selection model on management innovative enterprises is needed since the Korean government provides multi benefits to those selected enterprises. However, the selection model's propriety is suspicious because of the shortage of consideration of assessment items. In particular, the most important two assessment items, strategy and performance are suspected of multicollinearity because of high correlation scores. No consideration on multicollinearity among those items leads to erroneous selection which doubly counts the same components with different item names. The principle component analysis is applied to factor out the uncorrelated items. Using the resulted principle components, the new estimations are carried out. The comparison between estimated results from using principle components and non principle components shows that the present selection model overly considers the performance items compared to the real effect of items, which is a result of multicollinearity between performance and strategy.

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Distributed Video Compressive Sensing Reconstruction by Adaptive PCA Sparse Basis and Nonlocal Similarity

  • Wu, Minghu;Zhu, Xiuchang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제8권8호
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    • pp.2851-2865
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    • 2014
  • To improve the rate-distortion performance of distributed video compressive sensing (DVCS), the adaptive sparse basis and nonlocal similarity of video are proposed to jointly reconstruct the video signal in this paper. Due to the lack of motion information between frames and the appearance of some noises in the reference frames, the sparse dictionary, which is constructed using the examples directly extracted from the reference frames, has already not better obtained the sparse representation of the interpolated block. This paper proposes a method to construct the sparse dictionary. Firstly, the example-based data matrix is constructed by using the motion information between frames, and then the principle components analysis (PCA) is used to compute some significant principle components of data matrix. Finally, the sparse dictionary is constructed by these significant principle components. The merit of the proposed sparse dictionary is that it can not only adaptively change in terms of the spatial-temporal characteristics, but also has ability to suppress noises. Besides, considering that the sparse priors cannot preserve the edges and textures of video frames well, the nonlocal similarity regularization term has also been introduced into reconstruction model. Experimental results show that the proposed algorithm can improve the objective and subjective quality of video frame, and achieve the better rate-distortion performance of DVCS system at the cost of a certain computational complexity.

Quality Assessment of Curcuma longa L. by Gas Chromatography-Mass Spectrometry Fingerprint, Principle Components Analysis and Hierarchical Clustering Analysis

  • Li, Ming;Zhou, Xin;Zhao, Yang;Wang, Dao-Ping;Hu, Xiao-Na
    • Bulletin of the Korean Chemical Society
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    • 제30권10호
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    • pp.2287-2293
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    • 2009
  • Gas Chromatography-Mass Spectrometry (GC-MS) fingerprint analysis, Principle Components Analysis (PCA), and Hierarchical Cluster Analysis (HCA) were introduced for quality assessment of Curcuma longa L. (C. longa). The GC-MS fingerprint method was developed and validated by analyzing 33 batches of samples of C. longa from different geographic locations. 18 chromatographic peaks were selected as characteristic peaks and their relative peak areas (RPA) were calculated for quantitative expression. Two principal components (PCs) were extracted by PCA. C. longa collected from Guizhou and Fujian were separated from other samples by PC1, capturing 71.83% of variance. While, PC2 contributed for their further separation, capturing 11.13% of variance. HCA confirmed the result of PCA analysis. Therefore, GC-MS fingerprint study with chemometric techniques provides a very flexible and reliable method for quality assessment of C. longa.

PCA에 의한 도서분류에 관한 연구( I ) (A Study on the Classification of Islands by PCA ( I ))

  • 이강우
    • 수산경영론집
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    • 제14권2호
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    • pp.1-14
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    • 1983
  • This paper considers a classification of the 88 islands located at Kyong-nam area in Korea, using by examples of 12 components of the islands. By means of principal component analysis 2 principle components were extracted, which explained a total of 73.7% of the variance. Using an eigen variable criterion (λ>1), no further principle components were discussed. Principal component 1 and 2 explained 63.4% and 10.3% of the total variance respectively, The representation of the unrelated factor scores along the first and second principal axes produced a new information with respect to the classification of the islands. Based upon the representation, 88 islands were classified into 6 groups i. e. A, B, C, D, E, and F according to similarity of the components among them in this paper. The "Group F" belongs to a miscellaneous assortment that does not fit into the logical category. category.

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Mixed finite element model for laminated composite beams

  • Desai, Y.M.;Ramtekkar, G.S.
    • Structural Engineering and Mechanics
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    • 제13권3호
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    • pp.261-276
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    • 2002
  • A novel, 6-node, two-dimensional mixed finite element (FE) model has been developed to analyze laminated composite beams by using the minimum potential energy principle. The model has been formulated by considering four degrees of freedom (two displacement components u, w and two transverse stress components ${\sigma}_z$, $\tau_{xz}$) per node. The transverse stress components have been invoked as nodal degrees of freedom by using the fundamental elasticity equations. Thus, the present mixed finite element model not only ensures the continuity of transverse stress and displacement fields through the thickness of the laminated beams but also maintains the fundamental elasticity relationship between the components of stress, strain and displacement fields throughout the elastic continuum. This is an important feature of the present formulation, which has not been observed in various mixed formulations available in the literature. Results obtained from the model have been shown to be in excellent agreement with the elasticity solutions for thin as well as thick laminated composite beams. A few results for a cross-ply beam under fixed support conditions are also presented.

의료사고피해 구제제도의 제 모형 (Models of Social Relief Schemes for Medical Malpractice)

  • 문옥륜;이기효
    • 보건행정학회지
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    • 제2권1호
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    • pp.80-114
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    • 1992
  • Current compensation schemes for medical malpractice based on negligence is absolutely malfunctioning in Korea. Focussing on the reform of present tort systems for resolving medical malpractice disputes, this paper discusses the alternative models of the Social Relief Schemes for Medical Malpractice (SRSMM). Alternative models of SRSMM should fundamentally be based on either negligence or nofalult compensation principle. On the foundation of the previous relief principle, the SRSMM should be equupped with three major components-the preventio/reduction of the sharp increasing medical malpractice, the effective and efficient resolving process for malpractice disputes and the proper social financing scheme for compensation. The paper deals with pros and cons of the possible alternative models for reform centering on the three major components of the scheme. As conclusions, administrative arbitration machinaries and a compulsory fund for compensating the injured under the negligence principle are proposed to resolve the current problems Korea has faced.

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Orthogonalization principle for hybrid control of robot arms under geometric constraint

  • Arimoto, Suguru
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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    • pp.1-6
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    • 1992
  • A principle of "orthogonalization" is proposed as an extended notion of hybrid (force and position) control for robot manipulators under geometric endpoint constraints. The principle realizes the hybrid control in a strict sense by letting position and velocity feedback signals be orthogonal in joint space to the contact force vector whose components are exerted at corresponding joints. This orthogonalization is executed via a projection matrix computed in real-time from a gradient of the equation of the surface in joint coordinates and hence both projected position and velocity feedback signals become perpendicular to the force vector that is normal to the surface at the contact point in joint space. To show the important role of the principle in control of robot manipulators, three basic problems are analyzed, the first is a hybrid trajectory tracking problem by means of a "modified hybrid computed torque method", the second is a model-based adaptive control problem for robot manipulators under geometric endpoint constraints, and the third is an iterative learning control problem. It is shown that the passivity of residual error dynamics of robots follows from the orthogonalization principle and it plays a crucial role in convergence properties of both positional and force error signals.force error signals.

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우무가사리(Gelidium amansii)의 구충성분에 대하여(제 1 보) (Studies on the Anthelmintic constituents of Gelidium amansii.)

  • 서석수;홍승철
    • 약학회지
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    • 제6권2호
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    • pp.1-6
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    • 1962
  • Clinical tests revealed that the extracts of Gelidium amansii (Gelidiaceae) had a anthelmintic action and further examinations were made on the anthelmintic components of this seaweed. This anthelmintic principle is absorbed on alumina and eluted from it by alkali solution. The active principle is absorbed on activated carbon from aqueous extract and eluted from it by methanol and it is not adsorbed on Amberite IR-120(H-form). This anthelmintic effective fraction was prepared by the use of this properties. Action of the active principle of Gelidium amansii was examined pharmacologically. The active principle of Gelidium amansii was found to decrease the tensity, tonus and mobility of Eisenia foetida(Savigny) nerve muscles. The active principle of this effective fraction was submitted to paper chromatography and spots to ninhydrin were detected at Rf; 0.30-0.31(yellow), 0.26(violet), 0.2(violet), 0.14-0.13(violet), 0.9(orange) and 0.04(violet).

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산란 주령 및 중량 규격에 따른 계란의 주요 성분 및 내부 품질 비교 (Comparison of Principle Components and Internal Quality of Eggs by Age of Laying Hens and Weight Standard)

  • 이재청;김선효;선창완;김창호;정사무엘;이준헌;조철훈
    • 한국가금학회지
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    • 제40권1호
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    • pp.49-55
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    • 2013
  • 본 연구는 산란 주령과 중량에 따른 계란의 주요 성분과 내부 품질의 변화를 확인하기 위하여 수행되었다. Hy-Line Brown 품종의 18주령에서 63주령으로부터 계란을 주령별로 약 50개씩 총 2,140개를 수거하여 난각, 난황 및 난백의 중량과 난백 높이 그리고 Haugh unit을 측정하였다. 중량 규격이 높아짐에 따라 난각, 난황 및 난백의 중량은 증가하였으나, 난백 높이와 Haugh unit은 낮아짐을 나타내었다. 또한, 산란 주령이 경과함에 따라 난황은 증가하고, 난백 비율은 감소하는 경향을 나타내었으며, 산란 주령은 난각, 난황, 난백 및 전체 계란 중량과 정의 상관관계를 보였으나, 난백 높이와 Haugh unit과는 부의 상관관계를 나타내었다. 또한 계란 중량이나 주요 구성 성분의 중량이 증가함에 따라 난백 높이 및 Haugh unit은 감소하는 것으로 나타났다.